Description of problem:
After create a bootable usb disk using dd command,and do a installation on a  kvm-based VM,you will get  this AVC and a "no bootable device " on the VM screen  immediately .This is really annoying and I have to do "setenforce 0" to start my installation.
SELinux is preventing qemu-system-x86 from 'read' accesses on the file +usb:2-1:1.0.

*****  Plugin catchall (100. confidence) suggests   **************************

If you believe that qemu-system-x86 should be allowed read access on the +usb:2-1:1.0 file by default.
Then you should report this as a bug.
You can generate a local policy module to allow this access.
Do
allow this access for now by executing:
# grep qemu-system-x86 /var/log/audit/audit.log | audit2allow -M mypol
# semodule -i mypol.pp

Additional Information:
Source Context                system_u:system_r:svirt_t:s0:c519,c701
Target Context                system_u:object_r:udev_var_run_t:s0
Target Objects                +usb:2-1:1.0 [ file ]
Source                        qemu-system-x86
Source Path                   qemu-system-x86
Port                          <Unknown>
Host                          (removed)
Source RPM Packages           
Target RPM Packages           
Policy RPM                    selinux-policy-3.13.1-179.fc24.noarch
Selinux Enabled               True
Policy Type                   targeted
Enforcing Mode                Enforcing
Host Name                     (removed)
Platform                      Linux (removed) 4.5.0-0.rc7.git0.2.fc24.x86_64 #1
                              SMP Tue Mar 8 02:20:08 UTC 2016 x86_64 x86_64
Alert Count                   14
First Seen                    2016-04-27 10:42:08 CST
Last Seen                     2016-04-27 10:42:08 CST
Local ID                      0efbc2e3-0bfd-42db-ae87-072b38235fd3

Raw Audit Messages
type=AVC msg=audit(1461724928.915:445): avc:  denied  { read } for  pid=2865 comm="qemu-system-x86" name="+usb:2-1:1.0" dev="tmpfs" ino=17617 scontext=system_u:system_r:svirt_t:s0:c519,c701 tcontext=system_u:object_r:udev_var_run_t:s0 tclass=file permissive=0


Hash: qemu-system-x86,svirt_t,udev_var_run_t,file,read

Version-Release number of selected component:
selinux-policy-3.13.1-179.fc24.noarch

Additional info:
reporter:       libreport-2.6.4
hashmarkername: setroubleshoot
kernel:         4.5.0-0.rc7.git0.2.fc24.x86_64
type:           libreport

Potential duplicate: bug 1276873